Grassy weeds in winter cereals in southern Spain

Saavedra, Milagros Saavedra; Cuevas, J.; Mesa-García, J.; García‐Torres, L.

doi:10.1016/0261-2194(89)90024-0

Cited by 20 publications

(18 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to several surveys, Lolium sp have been found in more than 800 000 ha of cereal fields in Spain [9]. L. rigidum was present in more than 50% of the cereal fields of Catalonia [25], 24% in the Duero Valley [9] and 35% in Andalucia [28], being considered as the most abundant grass weed in the cereal fields of Catalonia and the Duero Valley. Several studies indicate that L. rigidum can be an extremely competitive weed in cereal crops [6,17,26].…”

Section: Introductionmentioning

confidence: 99%

Effects of crop and weed densities on the interactions between barley and Lolium rigidum in several Mediterranean locations

Izquierdo¹,

Guinjuan²,

Fernández‐Quintanilla³

et al. 2003

Agronomie

View full text Add to dashboard Cite

-The effects of both barley and Lolium rigidum densities on weed growth and spike production and on crop yield were examined in five field experiments carried out in the Mediterranean drylands of Spain and Western Australia. The aim was to check the consistency of the competitiveness of the crop in different environmental and management conditions. L. rigidum reduced barley yields in most of the experiments (between 0 and 85%), the number of ears per m 2 being the most affected. It was found that increasing the barley seeding rate did not reduce the crop losses but did limit weed biomass (between 5 and 61%) and spike production (between 24 and 85%). The variability observed in crop yield losses between sites and seasons was related to rainfall at the beginning of the season. The most sensitive component of yield to weed competition was the number of ears per plant.

show abstract

Section: Introductionmentioning

confidence: 99%

Effects of crop and weed densities on the interactions between barley and Lolium rigidum in several Mediterranean locations

Izquierdo¹,

Guinjuan²,

Fernández‐Quintanilla³

et al. 2003

Agronomie

View full text Add to dashboard Cite

show abstract

“…However in this area it is rare to find subspecies' ludoviciana. In contrast, in eastern Andalusia, where the two Avena sterilis subspecies coexisted, A. ludoviciana was more frequent and presented higher plant densities (Saavedra et al, 1989). However, both subspecies are clearly distinguishable by the sizes of their vegetative and reproductive traits.…”

Section: Introductionmentioning

confidence: 71%

“…sterilis has been reported as the most important grass weed in cereals, with 58.8% of the cereal fields being infested by this species (Saavedra et al, 1989), although infestations were widespread, densities were very low in most sites. However in this area it is rare to find subspecies' ludoviciana.…”

Section: Introductionmentioning

confidence: 99%

Competition between Avena sterilis ssp. sterilis and wheat in South Western Spain

Barroso

Alcántara

Saavedra

1970

Span. j. agric. res.

Self Cite

View full text Add to dashboard Cite

Avena sterilis spp. sterilis has different growth and demographic characteristics than other weedy taxa of Avena. Preliminary studies have shown that wheat yield losses caused by this species were larger than those produced by the spp. ludoviciana. These losses were estimated experimentally in 19 wheat fields distributed throughout western Andalusia. The relationship between A. sterilis spp. sterilis density per square meter and the wheat grain weight was estimated using several simple models. The results obtained conf irm that this weed species was tremendously competitive even at low densities, obtaining wheat yield losses up to 70 kg ha -1 panicle -1 m -2 . The potential crop yield of the field was considered as an important factor to estimate the yield losses. A relationship between the expected weed-free yield of wheat and the yield loss per panicle of A. sterilis spp. sterilis was used to determine the economic threshold. This threshold ranged from 4 to 81 panicles m -2 depending on the potential yield of each field. Farmers with high potential yields (> 6,000 kg ha -1 ) should treat their fields if A. sterilis density is above 10 panicles m -2 . Farmers with low potential yields (< 3,000 kg ha -1 ) should not applied any herbicide control to their fields whatever the infestation density. And if the potential yields are between 3,000 and 6,000 kg ha -1 they should estimate the economic threshold value from the exponential equation described in this work.Additional key words: economic threshold; linear model; weed-crop competition; weed density; wild oat; yield loss. ResumenCompetencia entre Avena sterilis subsp. sterilis y trigo en el suroeste de España.Avena sterilis spp. sterilis tiene diferente crecimiento y características demográficas que otros taxones de malas hierbas del género Avena. Estudios preliminares han demostrado que las pérdidas de rendimiento del trigo causadas por esta subespecie fueron mayores que las producidas por la subespecie ludoviciana. Estas pérdidas se estimaron de forma experimental en 19 campos de trigo distribuidos por el oeste de Andalucía. La relación entre la densidad de A. sterilis spp. sterilis por metro cuadrado y el peso del grano de trigo se estimó mediante modelos de regresión. Los resultados obtenidos confirman que esta especie de mala hierba fue tremendamente competitiva, incluso a bajas densidades, obteniéndose pérdidas de rendimiento del trigo de hasta 70 kg ha -1 panícula -1 m -2 . El rendimiento potencial del campo fue un factor importante para estimar las pérdidas de rendimiento. Con objeto de determinar el umbral económico, se estableció una relación entre el rendimiento esperado de trigo libre de malas hierbas y la pérdida de rendimiento por panícula de A. sterilis spp. sterilis. Dicho umbral económico osciló entre 4 y 81 panículas m -2 en función del potencial de rendimiento de cada campo. Rendimientos potenciales mayores de 6.000 kg ha -1 requerirán tratamiento cuando la densidad de A. sterilis supere las 10 panículas m -2 . Rendimientos potenciales...

show abstract

“…This success is achieved by the heterogeneity created by the different crops and their management systems (Joannon et al 2008), which impose different types and intensities of biotic and abiotic stresses on weeds (Liebman and Dyck 1993). In more recent years, weed control has mainly been through herbicide use (Saavedra et al 1989), but control methods such as crop rotation are regaining interest due to the increased pressure to develop sustainable control methods that have a limited environmental impact. An effective crop rotation deployment might thus limit, and in some cropping years even eliminate, the need for herbicide applications to control the dominant weed species.…”

Section: Introductionmentioning

confidence: 99%

Controlling annual weeds in cereals by deploying crop rotation at the landscape scale: Avena sterilis as an example

González-Díaz

Berg

Bosch

et al. 2012

Ecological Applications

View full text Add to dashboard Cite

Abstract. Weed control through crop rotation has mainly been studied in a nonspatial context. However, weed seeds are often spread beyond the crop field by a variety of vectors. For weed control to be successful, weed management should thus be evaluated at the landscape level. In this paper we assess how seed dispersal affects the interactions between crop rotation and landscape heterogeneity schemes with regard to weed control. A spatially explicit landscape model was developed to study both short-and long-term weed population dynamics under different management scenarios. We allowed for both two-and three-crop species rotations and three levels of between-field weed seed dispersal. All rotation scenarios and seed dispersal fractions were analyzed for both completely homogeneous landscapes and heterogeneous landscapes in which more than one crop was present. The potential of implementing new weed control methods was also analyzed. The model results suggest that, like crop rotation at the field level, crop rotation implemented at the landscape level has great potential to control weeds, whereby both the number of crop species and the cropping sequence within the crop rotation have significant effects on both the short-and long-term weed population densities. In the absence of seed dispersal, weed populations became extinct when the fraction of each crop in the landscape was randomized. In general, weed seed densities increased in landscapes with increasing similarity in crop proportions, but in these landscapes the level of seed dispersal affected which three-crop species rotation sequence was most efficient at controlling the weed densities. We show that ignoring seed dispersal between fields might lead to the selection of suboptimal tactics and that homogeneous crop field patches that follow a specific crop rotation sequence might be the most sustainable method of weed control. Effective weed control through crop rotation thus requires coordination between farmers with regard to cropping sequences, crop allocation across the landscape, and/ or the fraction of each crop across the landscape.

show abstract

Grassy weeds in winter cereals in southern Spain

Cited by 20 publications

References 1 publication

Effects of crop and weed densities on the interactions between barley and Lolium rigidum in several Mediterranean locations

Effects of crop and weed densities on the interactions between barley and Lolium rigidum in several Mediterranean locations

Competition between Avena sterilis ssp. sterilis and wheat in South Western Spain

Controlling annual weeds in cereals by deploying crop rotation at the landscape scale: Avena sterilis as an example

Contact Info

Product

Resources

About